PCV valve block off options

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LucyFord
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PCV valve block off options

Post by LucyFord »

I just moved to a oil catch can system where the two valve cover breathers and returns via the PCV vent. Now i have this PCV valve just sitting there. How do you guys typicaly block this thing off? Just a cap? Does someone know the thread size for i can buy a plug from mcmaster? Any suggestions?
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Legacy777
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Re: PCV valve block off options

Post by Legacy777 »

Can you elaborate what you did? You don't want to get rid of the PCV valve.

What about the vent on the back of the engine? What are you doing with that.

The breathers on the valve covers are to draw air into the crankcase. the main vent on the back of the engine block is where the oil vapors/blow by comes out and either enters the intake or the PCV valve. This vent on the engine block is where you want the catch can to tie into. Route the output of the catch can back to the intake and PCV valve. It needs to be tied to both.
Josh

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LucyFord
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Location: Utah

Re: PCV valve block off options

Post by LucyFord »

Both breathers have lines going to the top of the catch can. (They were spilling out oil everywhere when on track before we did this)

The bottom of the catch can goes to the vent of the engine (the oil from the valve covers would go back in through here and the positive pressure/vapors from blow by could still escape)

The can itself is open to the atmosphere so the the vents can still draw air into the crank
Last edited by LucyFord on Thu May 31, 2012 6:21 pm, edited 1 time in total.
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Legacy777
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Re: PCV valve block off options

Post by Legacy777 »

Was everything on the PCV system plumbed as stock before you added the catch can?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
LucyFord
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Location: Utah

Re: PCV valve block off options

Post by LucyFord »

Legacy777 wrote:Was everything on the PCV system plumbed as stock before you added the catch can?
Yes
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Legacy777
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Re: PCV valve block off options

Post by Legacy777 »

Hmmm. Well if you were getting oil out of the valve cover vents I'd say you had some pretty high lateral g forces.

If it was plumbed stock before, how was the oil being spilled? Was it just leaking at the hose/valve cover connection point?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
LucyFord
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Posts: 110
Joined: Fri May 27, 2011 3:14 pm
Location: Utah

Re: PCV valve block off options

Post by LucyFord »

Legacy777 wrote:Hmmm. Well if you were getting oil out of the valve cover vents I'd say you had some pretty high lateral g forces.

If it was plumbed stock before, how was the oil being spilled? Was it just leaking at the hose/valve cover connection point?

Ohh your right. I assumed the valve cover wasnt part of the PCV system (silly me). Yeah we had too long tubes going to a breather. I think we are pulling over 1g lat but i haven't seen dry test data to confirm that.


Anyways. Any suggestions on how to plug that guy off? I hate the look of caps on things. Would you know the thread?
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Legacy777
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Re: PCV valve block off options

Post by Legacy777 »

Sorry for the late reply, but any chance you could draw up a quick diagram in MS paint of how you have the PCV system setup, and what you exactly want to block off?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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